The invention relates to the field of digital communications, and in particular to a sync signal detector and a phase estimator for use in a digital television (DTV) receiver.
Within a few months television in North America will undergo a change as fundamental and sweeping as the advent of color. In November, 1998 broadcasters in large metropolitan areas will begin digital broadcasts which promise much sharper picture and sound than current systems provide. Called digital television (DTV), formerly referred to as high definition television "HDTV", the new system also has many features that are absent from conventional broadcasting, such as auxiliary channels for data and easy connection to computers in telecommunication networks.
The changeover from the current analog system to the new digital form has taken a number of years due to a need for uniformity on the system standards. Government officials, broadcasters and television manufacturers (collectively the "Grand Alliance") worked together to come up with a digital standard that would not render existing TV's immediately obsolete.
The system which the Grand Alliance decided upon transmits high quality video and audio data over a single 6 MHz channel. The system can deliver reliably about 19 MBPS of throughput in a 6 MHz terrestrial broadcasting channel and about 38 MBPS of throughput in a conventional cable television channel.
Now that the functional system level architecture has been selected by the Grand Alliance, the next step is to design and provide a low cost, reliable commercially realizable receiver that is compatible with the system level architecture defined by the Grand Alliance. This includes providing detector circuitry that accurately detects a data segment sync signal that separates packets of data in the data signal.